Chen Guei-san (陳貴珍), chairman of the Puli Swimming Association, said that the association assessed problems at last year's swimming carnival and believes parking will be problematic this year as well.

Chen said that the total number of participants had been limited to 20,000 this year.

"The fact that so many swimmers come and take part in the challenge will only encourage more international participants to come," Chen told the Taipei Times.

The association said that the oldest applicant this year is 76 years old and the youngest is just 10.

Hung Wei-hsin (洪維新), assistant director of the Sun Moon Lake National Scenic Area Administration, confirmed yesterday that the event had attracted so many visitors that all hotels and bed and breakfasts in the area around Sun Moon Lake were already fully booked.

To accommodate the transportation needs of tourists, the Nantou County Government has arranged hourly shuttle buses to take travelers from the lake area to the high speed rail station.

The Puli Swimming Association has been hosting the event for the past two decades.

Participants are required to swim 3km across Sun Moon Lake.

Several county-level officials and overseas guests will also join the participants in the swim, including Nantou County Commissioner Lee Chao-ching (李朝卿), Hualien County Commissioner Hsieh Sheng-shan (謝深山) and the mayor of West Valley City, Utah, Dennis Nordfelt.

Following the event, the Nantou County Government will also arrange races at Hohuanshan on Sept. 30.